فصلنامه مطالعات جغرافیایی مناطق خشک
پیاپی 32 (تابستان 1397)

In philosophy of science, particularly in the human sciences, concepts have Multiple meanings even have contradictory definition from ontological and epistemological aspects in different philosophical schools. Therefore, determination The theoretical framework for understanding of fundamental concepts, are most important in the study and understanding of the concepts in human sciences. One of the key concepts and paradigms in Geographical Sciences, concept of space and its planning, logistics, and general changes in the governance space and how to explain it. In this article endeavors theoretical concept of geographical space as a fundamental concept of geographical sciences be explained in existentialism school. So, this is a qualitative research and data has been collected with using of valid library documentations and this article is kind of Fundamental and qualitative research and for data analyzing method was used from descriptive and analytical approaches. In the first step have been struggled with using literature and theoretical resources to define the concept of space and existentialism. Then, by combining these two concepts, is provided redefining the concept of space. Finding research reveals that in this school the emergence of space in the structural and functional aspects appears from mental activity therefore space has temporal – place nature.

Due to the fact that our country has entered a long period of drought, water supply and optimal use of it, especially in rural areas, have been a priority. The most important objectives of the present research are the feasibility of providing part of the water consumed by the villages through the catchment areas of the basin, which will be carried out through appropriate training and dissemination of culture. The researcher hopes that by promoting the culture of optimal use of atmospheric precipitation, in addition to providing part of the needs of villagers, especially villagers who are water supplied by tankers, they will reduce the pressure on groundwater resources that are expose to atmospheric hazards.

This study is practical in purpose, descriptive and analytical in essence and methodology. For gathering information, two methods of fieldwork and non- fieldwork and fixing sample volume using Cochran formula, equivalent to 251 persons. The main tool is questionnaire, with total 28 questionnaires, which has been distributed among the rurals systematically by chance, and then the information was gathered. Sample villages under study include 6 villages selected out of 57 villages of over 20 families.

not only the rurals are highly motivated to cooperate in performing this project, but also they understand the importance and operation of this project as a useful and low costs method for controlling the water shortage crisis and decreasing the support to the concentrated water supply systems to the remote places such as pipe water, dam, well, subterranean canal, water supply tank, and reviving stable level and They need local and private organizations’ help and support in resolving the problems.Solution: Among the strategies emphasized in this paper, the creation of the spirit of participation in the villages and the dissemination of culture have been the optimal exploitation of atmospheric rainfall through public education.

Re-use of unconventional water (sewage effluent) is one of the plans that can reduce the effects of desertification and it can provide integrated management of water resources in desert. In this direction, it is very important, investigating the effects of urban Wastewater on Soil Properties. The purpose of this research, is Investigating the Effects of sewage effluent of Sabzevar on Soil Properties in the desert areas Barabad of city Sabzevar. To do this, Sampling was done Through Method of Systematic- randomized from the control areas and irrigation areas with wastewater. Results of chemical properties showed, amount of calcium, magnesium, acidity and neutralizing content is without significant change and electrical conductivity, sodium, chlorine and sodium absorption Ratio decreased significantly compared to the control area. Results of Fertility properties showed, significant reduction is in the amount of organic carbon, phosphorus and potassium absorbed in the rstored area compared to the control area. Eventually. Planting plan with wastewater in the studied area showed, In terms of changes in soil properties, There are positive effects and Haloxylon aphyllum Than Atriplix canesences and Nitraria Schoberi evaluated  mre appropriately in terms of improving soil conditions

An examination of urban rural links in each location requires the analysis of streams linking urban and rural settlements. Such links under the heading of "flow of space" are embodied in the framework of a network approach and include flows of capital, persons, goods, information, innovation, technology, and so on. These flows include a process that, in appropriate conditions They can bring together rural urban associations that not only lead to the establishment of spatial networks, but also provide the basis for the formation of social networks. These flows have multiple components and effectiveness, appear in different spatial links and hence require their own specific policies. Since the strengthening of rural urban links with the goal of economic development and poverty reduction, it depends on the geographical, socio-economic and ecological conditions of the local and regional. In line with the discussed issues, this paper deals with the case study of Gomishan city in the framework of structural functional theory and in the framework of descriptive-analytic method to study the spatial flows in the border regions of Golestan province. The statistical population of this study included 29 border villages located in the city of Gomishan. All of these villages were studied. The results show that spatial currents are related to the urban rural development of Gomishan area. Nevertheless, the influence of some spatial flow In the area of ​​Gomishan is zero.

 Droughts in Zabul have cause the erosion of human habitats, especially in areas exposed to sand accumulation. Creating an optimal urban form can be a way to counteract its destructive effects.

in this paper, the research method is based on the partial air flow simulation method and the city form survey. The goal is to find the most optimal form of residential buildings to reduce pollutant emissions in the Zabul city. The building forms was investigated by airflow simulation using Flow 3D fluid simulation software. A flat ground with an initial configuration was selected for the model. And each time the air flow behavior was tested in different models. In this study, the relationship between urban wind speed and morphological parameters such as dimensions, building geometry and building density was investigated and it was concluded that urban wind speed can help reduce sand stagnation by considering appropriate values ​​of these parameters. Results and

Therefore, by studying the urban shape and making arrangements such as building height from the ground, determining the proper length of the urban block and how the adjacent buildings can be connected, the accumulated particles can be discharged to the city as permitted by changes in wind speed.

Due to its mobility and ability to move and its direct impact on residential areas and various developmental activities, the Ergs are of major importance in the desert areas, so monitoring of those is very important. Considering that the use of supervised and unguarded methods is considered as one of the most common methods in determining and monitoring land uses, in this research, the accuracy of different classification methods in the monitoring of Jazmourian regs was investigated. In this research, in order to evaluate the accuracy of different classification methods in determining the type of usage of the study area, especially the regs, satellite image of the Landsat 8, OLI sensor in 2017 has been used. First, the area of ​​the regs prepared manually using Google Earth and Topography Map of the region, and then in the ENVI software, the land use type of ​​the study area was determined by different supervised (Maximum Probability, Minimum Distance to Mean, equilibrium, Parallelepiped) and unsupervised methods (K-mean) and then the plotted area using two point and surface methods were compared with the area determined by different classification methods, and the accuracy of each method was measured. Due to the similarity of the reflection type of Landsat images in desert areas, the results are of little precision, so that the evaluation results indicate that in the point and surface method, maximum probability classification, with a total accuracy of 64.9 % and 53% has the highest accuracy and the k-mean method with a total accuracy of 15.5% and 17% has the lowest accuracy, respectively. So, in order to monitor the type of land use, including desert areas regs, a different kind of satellite imagery or other classification algorithms should be used.